Reamer.



G; G. MITOHEI REAMER.

APPLICATION FILED SEPT. 6, 191 2.

rat ntedmay z'r, 1913;

cameras 0. terrorist, or LYNDH-URST, NEW anasay.

RE-AMER.

Specification of Letters Patent.

Patented May 2'7, 1913.

Application filed September 6,1912. Serial No. 718,856.'

To all whom it may concern -Be it known that I, CHARLES C. MIToHnL, a citizen of the United States, residing at Lyndhurst, in* the county of Bergen and State of-New Jersey, have invented acertain new and useful Improvement in Beamers, of which the following is a specifica tion.

The invention relates to reamers of the, expanding type, and is designed more especially for service in deep-well drilling,

In drilling hard rock the drill gradually diminishes exteriorly by wear and it is sometimes necessary to ream the bore to permit the well-casing to be driven, and frequently in drilling tliroughhard rock into a pocket or stratum of soft material, as sand, the drill in breaking through the lower por-' tion of the rock leaves an irregular opening which must be shaped cylindrically to re-' ceive the casing. The improved reamer is" intended for such service, and the object of the invention is to provide a strong, simply constructed tool of this character which may be easily introduced in the bore, lowered to the required depth, and expanded positively at the point to be reamed, and easily and positively collapsed for withdrawal.

The invention consists in certain novel features of construction and arrangement by which the above objects are attained, to'be hereinafter described.

'The accompanying drawings form a part of this specification and show an approved form of the-invention.

Figure 1 is a vertical central section through the improved reamer, in the expanded condition, partly in elevation, :and

' ig.'2 is'a similar view showing the reamer collapsed. Fig, 3 is a face view of the bottom of the reamer. Fig. 4-is a transverse section, taken on the line 4 4.- in Fig. 1, and Fig. 5 is a corresponding section on the line i in Fig. 2. Fig. 6 is a side view of one of the cutters. Fig. 7 is a face view of the exterior of the same, andFig.- 8 is a corresponding top view.

Similar letters of reference indicate the same parts in all the figures. I

A is the spindlebox comprising a hollow cylindrical body having a solid head A drilled and tapped to receive the screwthreaded spindle B on the lower end ot a shank B and having the lower interior face of the head A adapted to serve as azshoul; derA or abutment for an adjustable collar C on the spindle. On the lower end of the spindle-box is secured the tubular cutterbox D having a series of'vertical slots 1d and closed at the lower end by a plate D 'V'Vithin the cutter-box are the cutter-bars E arranged segmentally about. the axial line of the box'and each having a blade or cutter E engaged in one of the slots. The inner facesof' the cutter-bars, are curved and also inclined downwardly to match to the surface of a long cone F secured to the-lower end of the spindle B and raised and lowered in. the cutter boxby the advance and recession of the spindle due to the rotation of the latter in the screw-threaded head A by turning the shank B In introducing the reamer into the bore,

the shank is turned and the cone thus raised until the collar C strikes the shoulder A thus partially withdrawing the cone from the cutter 'box and permitting the cutterbars to inove'inward'ly sufiiciently to bring the -blades within the circumference of the cutter-box while maintaining engagement with the slots. In this condition, shown in Fig. 2, the tool is lowered to the required depth' in the well-bore,and the shank then turned to force the cone downward-lyin the cutter-box and the cutters radially outward through the slots therein. By continuing intosufficiently strong frictional contact with the cutter-bars to cause the cutter-box to partake in the rotation and turn with the rotation of the shank the cone is forced the shank and spindle, with the cutting blade of each cutter-barf projected fully.

through its slot, as in Fig. 1, and acting upon the interior ofthe well-bore. A reversal of rotation raises the cone, releases the cutter"v bars and their 'box and permits them to assume the collapsed position ready for withdrawal from the well.

The cutter-box is attached to.the spindlebox by screw-threads at 11 thus permitting the cutter-box to be removed and'the substitution of another of larger diameter, to be operated by the same or another cone, as will be understood.

A central opening 03 in the plate D permits material in the cutter-box to escape, and

is preferablylarge enough to permit the lower end of the cone to pass in case the cone should be forced downwardly far enough to strike the plate and thus arrest its move ment, and holes d (Pare provided to receive pins on a suitable wrench, not shown, by

Y which the plate may be removed and replaced in assembling the parts.

The collar C is threaded to match the spindle and -may be adjusted thereon to limit the rise of the cone and thus determine the amount of inward movement permitted to the cutters relatively to theirfinclosing cutter-box. Set screws C are provided to insure the position of the collar, and a pin Gr extending transversely through the lower end of the spindle and the screw-threaded extension 1 of the, cone F prevents accidental separation at this point'in the operas tion of retracting the cone[ The cutter-bars are segmental in crosssection, having their outer faces E on which the narrow blades or cutters E are carried,

. curved to match to the interior of the cylindrical cutter-box, and their inner faces 'E? curved and tapered to match to the surface of the conewhen the latter is fully down and the outer faces E in firm contact with the interior of the cutter-box, thus insuring solidity during thereaming operation with strong frictional contact between the cone and bars. The edges of'the blades are preferably inclined downwardly so their radial -.projection is slightly greater at the upper portion to permit the reamin to be performed gradually as the tool is fed downward in the bore.

engagement withthe cutter-bars sufliciently to hold them in place with their blades engaged each in its respective slot, and prevent the inward escape or displacement of each.

Modifications may be made within the scope of the claims, in the forms and proportions of the parts. A greater or-less number of cutters may be employed, and the shape of the blades may be changed as the character of the work may dictate.

1. In a tool of the character 'set forth, a cutter-box having a series of radial slots therein, a'spind'le-box carried by said cutterbox, a series of cutterbars in said cutterbox and havingblades engaged in said "slots; a screw-threaded spindle engaged in said spindle-boxaand arranged to be rotated, and a cone on said spindle constructed when moved downwardly by the action ofthe screw-threads on said spindle to force said cutter-bars and blades outwardly and at the completion of such downward movement to engage said cutter-bars frictionally and rotate said cutter-box and blades.

2. In a tool of the character set forth, a cutter-box having a series of radial slots therein, a spindlebox ,carried by said cutterbox, an internal shoulder on said spindlebox, a series of cutter-bars in said cutterboX and having blades engaged in said slots, a screw-threaded spindle engaged in said spindle-box andarranged to be rotated, and a cone on said spindle constructed when moved downwardly by the action of the screw-threads on said spindle to force said cutter-bars and blades outwardly and at the completion of such downward movement to engage said cutter-bars frictionally and rotate said cutter-box and blades, and a-collar on said spindle arranged to strike said shoulder and limit the upward movement of said cone.

3. Ina tool of the character set forth, a cutter-box having a series of radial slots therein, a spindle-box carried by said cutterboX, an internal shoulder on said spindle- --boX, a, series of cutter-barsin said cuttera screw-threaded spindle engaged in said It will be noted that the cone is always in spindle-box and arranged to be rotated, a

cone on said spindle constructed when moved downwardly by the action of the screw-threads on said spindle to force said cutter-bars and blades outwardly and at the tompletio-n of such downward movement to :engage said cutter-bars frictionally and rotate said cutter-box and blades, a collar on said spindle arranged to strike said shoulder and limit the. upward movement of said cone, and means for adjusting said collar on said spindle relatively to said shoulder.

I In testimony that I claim the invention above setforth I allix my signature,'in presence of two witnesses.

-: CHARLES C. MITCHEL. 

